Journal of Resources and Ecology ›› 2020, Vol. 11 ›› Issue (3): 322-328.DOI: 10.5814/j.issn.1674-764X.2020.03.010

• Ecosystem Responses to Climate Change • Previous Articles    

Comparative Study of the Impact of Drought Stress on P.centrasiaticum at the Seedling Stage in Tibet

ZHANG Guangyu1,2,3, WANG Jiangwei1,2,3, ZHANG Haorui1,2,3, FU Gang1,2, SHEN Zhenxi1,2,*()   

  1. 1. Lhasa Plateau Ecosystem Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
    2. Engineering and Technology Research Center for Prataculture on the Xizang Plateau, Lhasa 850000, China
    3. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2020-01-14 Accepted:2020-02-18 Online:2020-05-30 Published:2020-06-16
  • Contact: SHEN Zhenxi
  • Supported by:
    The National Key Research and Development Program of China(2016YFC0502005);The Tibet Science and Technology Major Projects of the Pratacultural Industry(XZ201901NA03);The Lhasa Industrial Integration Project(XCKJ004);Research and Demonstration on the De-velopment Model of Forage Industry in Dagze County(LSKJ2018006)

Abstract:

Pennisetum centrasiaticum is widely distributed in arid and semi-arid areas of Tibet. Its rhizome system is developed and has strong resistance to adversity. In this study, the physiological characteristics and drought resistance of P.centrasiaticum seedlings from 12 drought-stressed sites in Tibet were examined at the Lhasa Plateau Ecosystem Research Station of the Chinese Academy of Sciences. PEG-6000 solution with five levels of water potential (0, -0.7, -1.4, -2.1, and -2.8 MPa) was used to simulate drought stress, and malondialdehyde (MDA), proline (Pro) and chlorophyll contents were determined. The balance between production and elimination of reactive oxygen species in P.centrasiaticum was destroyed, leading to membrane lipid peroxidation and the production of MDA, and accelerating the decomposition of chlorophyll. P.centrasiaticum absorbed water from the outside to resist drought by secreting proline and other osmotic regulating substances. The Pro and chlorophyll contents in P.centrasiaticum showed a temporary rising trend, and then decreased with the decrease in water potential. MDA content increased with the decrease in water potential. By using the membership function method, the drought resistance of P.centrasiaticum seedlings from the 12 areas was evaluated, and the results showed that the drought resistance at the sites went from strong to weak in this order: Xietongmen > Linzhou > Sog > Damxung > Tingri > Namling > Gyirong > Linzhi > Purang > Dingjie > Longzi > Sa’gya. The drought resistance of P.centrasiaticum was strong in Xietongmen, Linzhou and Sog. Whether P.centrasiaticum from these three areas is suitable for cultivation in arid and semi-arid areas of Tibet needs further study.

Key words: Tibet, P.centrasiaticum Tzvel., seedling stage, physiological characteristics, drought resistance